Structural and magnetic properties of SrLa1

Structural and magnetic properties of SrLa1-xNaxMn2O5 compounds with
0.1 ≤ x ≤ 0.3
M. Mohamed1, N. Rammeh2, A. Kabadou1, A. Van der Lee3
1 Laboratoire des Sciences des Matériaux et de l’Environnement, Département de chimie,
Faculté des Sciences de Sfax, 3000 Sfax, Tunisia.
2Laboratoire de Physico-Chimie des Matériaux Minéraux et leurs Applications, Borj Cedrea,
Tunisia
3Institut Européen des Membranes, Université de Montpellier II, France
Abstract. In this work, the synthesis and physico-chemical characterizations of new
brownmillerite oxides SrLa1-xNaxMn2O5 (0.1 ≤ x ≤0.3) were investigated. These materials
were elaborated using the solid state reaction method at high temperature. X-ray diffraction
study showed that all our synthesized samples are single phase and crystallize in the
orthorhombic system with Pnma space group. This structure can be described as an oxygen –
deficient perovskite, resulting in a sequence of regular alternating layers of corner –sharing
BO6 octahedra (O) and BO4 tetraedra (T) according to the axis b. In order to confirm the
chemical formula of these structures, scanning electronic microscopy was used.
Magnetization measurements versus temperature in a magnetic applied field of 0.05 T
indicate that our investigated samples display a paramagnetic-ferromagnetic transition. the
Curie temperature TC decrease with Na content.
Key words. Brownmellirite oxides, solid state reaction, X-ray diffraction, Rietveld
refinement, cationic substitution, Magnetization measurements